Fusion protein from feline leukaemia virus GP70 as vaccine

Abstract

A vaccine against feline leukaemia virus (FeLV) comprises a protein formed of two proteins derived from FeLV gp70 which are not adjacent in the native protein, particularly VR1 and VR5 and effective fragments thereof. VR5 is preferably attached to the carboxy terminus of VR1. A co-protein such as GST or β-galactosidase may be attached to the terminus of the fused protein, such as to stabilize and solubilize the fused protein. Attachments to the carboxy terminus may reduce the immunogenicity.

We claim: 
     
       1. An immunogenic fused recombinant protein which comprises a feline leukemia virus (FeLV) gp70 VR5 sequence fused to the carboxy terminus of a FeLV gp70 VR1 sequence, wherein the VR5 sequence has the sequence of SEQ ID NO: 6, and the VR1 sequence has the sequence of SEQ ID NO: 4. 
     
     
       2. A fused recombinant protein according to claim 1 which further comprises the sequence of an antigenic co-protein, said antigenic co-protein sequence attached to the amino terminus of said fused protein sequence. 
     
     
       3. A fused protein according to claim 2 wherein the co-protein sequence is glutathione-S-transferase of β-galactosidase. 
     
     
       4. A vaccine formulation which comprises the fusion protein of claim 1 together with a pharmaceutically acceptable carrier. 
     
     
       5. A vaccine formulation which comprises the fusion protein of claim 2 together with a pharmaceutically acceptable carrier.